Bernie Sanders inadvertently raises a critical question as Republicans pursue reform.

Vermont Socialist Sen. Bernie Sanders deplored the actions of his former campaign volunteer James T. Hodgkinson, who was killed after opening fire on participants at a congressional baseball practice for Republicans on June 14. More recently, Mr. Sanders has been accusing his Republican colleagues of hatching a plan that will result in thousands of deaths.

The anti-Trump ”resistance,” still smarting from its recent loss in a Georgia House race, has apparently decided that it needs someone more radical than Rep. Nancy Pelosi (D., Calif.) to lead the opposition to GOP health care reforms. So the organization MoveOn.org has been staging a multi-state tour with Mr. Sanders as the headliner. The basic Sanders argument, which he has been articulating in various fora in recent days, is that fewer people on government insurance plans will mean more people dying. It seems likely that any health reform plan that makes it to the President’s desk will no longer force people to buy ObamaCare plans, and will give states at least some flexibility in choosing not to provide insurance to people who aren’t sick, aren’t poor and don’t have children. But will fewer people on government-mandated insurance plans automatically make them less healthy? Mr. Sanders appears to be convinced. He tweeted on Friday: “Let us be clear and this is not trying to be overly dramatic: Thousands of people will die if the Republican health care bill becomes law.” Asked to defend such remarks on NBC’s “Meet the Press” on Sunday, Mr. Sanders said:

I wish I didn’t have to say it. This is not me. This is study after study making this point. It is common sense. If you have cancer and your insurance is taken away from you, there is a likelihood you will die and certainly a likelihood that you will become much sicker than you are today. That’s the fact. Unpleasant, but it’s true.

Speaking of studies, all of America has been participating in an experiment since 2010 to see if a federal effort to extend government-mandated insurance coverage to millions more people can improve our lives. Last year the Obama Administration bragged that 20 million adults had gained health insurance as a result of Mr. Obama’s so-called Affordable Care Act. Given the Sanders logic, one might have expected to see a corresponding improvement in public health. But so far evidence that ObamaCare made us healthier has proven elusive, to say the least. In December the New York Times was among the many news outlets that had to share the embarrassing news: American life expectancy is in decline for the first time since 1993, when H.I.V.-related deaths were at their peak. But this time, researchers can’t identify a single problem driving the drop, and are instead pointing to a number of factors, from heart disease to suicides, that have caused a greater number of deaths. A study on mortality rates released on Thursday by the National Center for Health Statistics showed that Americans could expect to live for 78.8 years in 2015, a decrease of 0.1 from the year before. The overall death rate increased 1.2 percent — that’s about 86,212 more deaths than those recorded in 2014. Dr. Peter Muennig, a professor of health policy and management at Columbia University’s Mailman School of Public Health, said in an interview that the decline was a “uniquely American phenomenon” in comparison with other developed countries, like Japan or Sweden. “A 0.1 decrease is huge,” Dr. Muennig said. “Life expectancy increases, and that’s very consistent and predictable, so to see it decrease, that’s very alarming.” It sure is. One thing on which researchers seem to agree is that there has been a deterioration in the health of middle-class whites. Why is this group seeing higher mortality rates? In a recent paper for the Brookings Institution, Nobel Prize-winning economist Angus Deaton and his Princeton colleague Anne Case write: We propose a preliminary but plausible story in which cumulative disadvantage over life, in the labor market, in marriage and child outcomes, and in health, is triggered by progressively worsening labor market opportunities at the time of entry for whites with low levels of education. Much of Mr. Deaton’s research over the years has examined the way that people around the world get healthier as they get wealthier. Republicans should note that expanding employment is a great way to improve wellness. This is of course the opposite of the agenda embedded in ObamaCare, which discouraged employment. It’s hard to tell if Mr. Sanders will regret raising the question of whether government insurance programs are the key to health and longevity. But it’s an argument he is not going to win.

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